And reference CSS class names by requiring the specific style into your javascript:

var style =require('./title.css');

<h1 className={style.title}>Yo</h1>

Note: enabling modules does so for every stylesheet in your project, so it's all-or-nothing. Even the files you don't require will be transformed into CSS modules (aka will have obfuscated class names, like turn .title into ._title_fdphn_1).

Dependencies

You can pass options for progeny which retrieves dependencies for the input CSS file.

For example, if you use postcss-partial-import plugin, your CSS files
prefixed with underscore and have .css extension. In this case, you need pass to progeny prefix option, so brunch can
properly rebuild your partials on their change.